Method for manufacturing semiconductor device

ABSTRACT

To provide a method for manufacturing a highly-reliable semiconductor device, which is not damaged by external local pressure, with a high yield, a semiconductor device is manufactured by forming an element substrate having a semiconductor element formed using a single-crystal semiconductor substrate or an SOI substrate, providing the element substrate with a fibrous body formed from an organic compound or an inorganic compound, applying a composition containing an organic resin to the element substrate and the fibrous body so that the fibrous body is impregnated with the organic resin, and heating to provide the element substrate with a sealing layer in which the fibrous body formed from an organic compound or an inorganic compound is contained.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for manufacturing asemiconductor device having a semiconductor element formed using asingle-crystal semiconductor substrate or an SOI substrate.

2. Description of the Related Art

Currently, it is important to make various devices, such as wirelesschips and sensors, into a thinner shape in miniaturizing products, andthe technique and the application range spread rapidly. Such variousdevices which are made thin are flexible to some extent and thus thedevices can be provided for an object having a curved surface.

In Reference 1 (Japanese Published Patent Application No. 2004-78991), asemiconductor device is disclosed in which, a semiconductor chip withthe size of less than or equal to 0.5 mm is embedded in paper or afilm-like medium, so that tolerance for bending and concentrated loadingis improved.

SUMMARY OF THE INVENTION

However, in the case of a semiconductor device with a built-in (on-chip)antenna which is incorporated in a chip, the size of the antenna issmall when the area occupied by the chip is small, leading to a problemof a short communication distance. In the case where a semiconductordevice is manufactured such that an antenna provided on a paper or afilm medium is connected to a chip, poor connection is made and yield isreduced when the size of the chip is small.

In view of the above, the present invention provides a method formanufacturing a highly-reliable semiconductor device, which is notdamaged by external local pressure, with a high yield.

It is an aspect of the present invention that a semiconductor device ismanufactured by forming an element substrate having a semiconductorelement formed using a single-crystal semiconductor substrate or an SOIsubstrate, providing the element substrate with a fibrous body formedfrom an organic compound or an inorganic compound, applying acomposition containing an organic resin to the element substrate and thefibrous body so that the fibrous body is impregnated with the organicresin, and heating to provide the element substrate with a sealingsubstrate containing the fibrous body formed from an organic compound oran inorganic compound.

It is another aspect of the present invention that a semiconductordevice is manufactured by forming an element substrate having asemiconductor element formed using a single-crystal semiconductorsubstrate or an SOI substrate, applying a composition containing anorganic resin to the element substrate, providing a fibrous body formedfrom an organic compound or an inorganic compound over the elementsubstrate and the organic resin so that the fibrous body is impregnatedwith the organic resin, and heating to provide the element substratewith a sealing substrate containing the fibrous body formed from anorganic compound or an inorganic compound.

The thickness of the element substrate is preferably greater than orequal to 1 μm and less than or equal to 80 μm, more preferably greaterthan or equal to 1 μm and less than or equal to 50 μm, greater than orequal to 1 μm and less than or equal to 20 μm, and still more preferablygreater than or equal to 1 μm and less than or equal to 10 μm, orgreater than or equal to 1 μm and less than or equal to 5 μm. Thethickness of the sealing layer is preferably greater than or equal to 10μm and less than or equal to 100 μm. With such thicknesses, asemiconductor device which can be curved can be manufactured.

The fibrous body is a woven fabric or a nonwoven fabric which useshigh-strength fiber of an organic compound or an inorganic compound. Thehigh-strength fiber is specifically fiber with a high elongation modulusor fiber with a high Young's modulus.

Further, as the organic resin, a thermoplastic resin or a thermosettingresin can be used.

Using high-strength fiber as the fibrous body, even when local pressureis applied to a semiconductor device, the pressure is dispersedthroughout the fibrous body; accordingly, partial stretching of thesemiconductor device can be prevented. That is, destruction of a wiring,a semiconductor element, or the like which is caused by partialstretching thereof, can be prevented.

In accordance with the present invention, a highly-reliablesemiconductor device which is not easily damaged by external localpressure can be manufactured with high yield.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1A to 1D are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 2A to 2C are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 3A to 3D are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 4A to 4C are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 5A to 5C are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 6A and 6B are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 7A to 7C are cross-sectional views illustrating a manufacturingmethod of a semiconductor device of the present invention;

FIGS. 8A and 8B are top views each illustrating a fibrous body which canbe applied to the present invention;

FIGS. 9A to 9D are top views each illustrating an antenna which can beapplied to the present invention;

FIGS. 10A and 10B are a perspective view and a cross-sectional view,respectively, each of which illustrates a semiconductor device of thepresent invention;

FIG. 11 is a diagram illustrating a semiconductor device of the presentinvention;

FIGS. 12A to 12E are perspective views each illustrating an applicationexample of a semiconductor device of the present invention;

FIG. 13 is a diagram illustrating a semiconductor device of the presentinvention; and

FIGS. 14A to 14E are views each illustrating an electronic device towhich a semiconductor device of the present invention can be applied.

DETAILED DESCRIPTION OF THE INVENTION Embodiment Mode

Embodiment Modes of the present invention will be explained below withreference to the accompanying drawings. However, the present inventioncan be implemented in various different modes, and it will be readilyappreciated by those skilled in the art that various changes andmodifications of the modes and details are possible, unless such changesand modifications depart from the content and the scope of theinvention. Therefore, unless such changes and modifications depart fromthe scope of the invention, they should be construed as being includedtherein. Note that identical portions or portions having the samefunction in all figures for explaining embodiment modes are denoted bythe same reference numerals and detailed descriptions thereof areomitted.

Embodiment Mode 1

In this embodiment mode, a method of manufacturing a semiconductordevice which is not easily damaged by external local pressure with highyield will be described with reference to FIGS. 1A to 1D.

As shown in FIG. 1A, an antenna 112 and an element substrate 1102 havinga semiconductor element formed using a single-crystal semiconductorsubstrate or an SOI substrate are formed. Next, a fibrous body 113 isprovided over the element substrate 1102 and the antenna 112.

As typical examples of a semiconductor element included in thesemiconductor substrate 1102, an active element such as a MOStransistor, a diode, or a nonvolatile memory element, and a passiveelement such as a resistor element or a capacitor element can be given.As a single-crystal semiconductor substrate, a single-crystal siliconsubstrate having n-type or p-type conductivity (a silicon wafer), or acompound semiconductor substrate (e.g., a GaAs substrate, an InPsubstrate, a GaN substrate, an SiC substrate, a sapphire substrate, or aZnSe substrate) is preferably used. Alternatively, an SOI (Silicon OnInsulator) substrate may be used. As the SOI substrate, the followingsubstrate may be used: a so-called SIMOX (separation by implantedoxygen) substrate which is formed in such a manner that after an oxygenion is implanted into a mirror-polished wafer, an oxide layer is formedat a certain depth from the surface by high-temperature annealing andeliminating defects generated in a surface layer, or an SOI substrateformed by using a technique called a Smart-Cut method in which an Sisubstrate is cleaved by utilizing growth of a minute void, which isformed by implantation of a hydrogen ion, by thermal treatment; anELTRAN (epitaxial layer transfer: a registered trademark of Canon Inc.)method; or the like. The thickness of the element substrate 1102 ispreferably greater than or equal to 1 μm and less than or equal to 80μm, more preferably greater than or equal to 1 μm and less than or equalto 50 μm, still more preferably greater than or equal to 1 μm and lessthan or equal to 20 μm, still more preferably greater than or equal to 1μm and less than or equal to 10 μm, still more preferably greater thanor equal to 1 μm and less than or equal to 5 μm. When the elementsubstrate is formed to have such a thickness, a semiconductor devicecapable of being curved can be manufactured. The area of a top surfaceof the semiconductor device is preferably greater than or equal to 4mm², more preferably greater than or equal to 9 mm².

When at least a MOS transistor, a resistor, a capacitor element, awiring and the like are formed in the element substrate 1102, amicroprocessor (MPU) which controls other devices and calculates andprocesses data can be manufactured. The MPU includes a CPU, a mainmemory, a controller, an interface, an I/O port, and the like.

Further, in a case where at least a memory element and a MOS transistoris formed in the element substrate 1102, a memory device can bemanufactured as a semiconductor device. As the memory element, anonvolatile memory element including a floating gate or a charge storagelayer; a MOS transistor and a capacitor element connected to the MOStransistor; a MOS transistor and a capacitor element including aferroelectric layer which is connected to the MOS transistor, an organicmemory element in which an organic compound layer is interposed betweena pair of electrodes; or the like can be given. As semiconductor deviceshaving such memory elements, memory devices such as DRAM (Dynamic RandomAccess Memory), SRAM (Static Random Access Memory), FeRAM (FerroelectricRandom Access Memory), mask ROM (Read Only Memory), EPROM (ElectricallyProgrammable Read Only Memory), EEPROM (Electrically Erasable andProgrammable Read Only Memory), and flash memory can be given.

In a case where at least a diode is formed in the element substrate1102, a light sensor, an image sensing, a solar battery, or the like canbe manufactured as a semiconductor device. As a diode, a photodiode suchas a PN diode, a PIN diode, an avalanche diode, or a Schottky diode, orthe like can be given.

Further, in a case where a MOS transistor which is at least included inthe element substrate 1102 is formed and an antenna electricallyconnected to the MOS transistor is formed over the element substrate1102; as a semiconductor device, an ID tag, an IC tag, an RF (RadioFrequency) tag, a wireless tag, an electronic tag, an RFID (RadioFrequency Identification) tag, an IC card, an ID card, or the like(hereinafter referred to as RFID), which can communicate data wirelesslycan be manufactured. Note that a semiconductor device of the presentinvention includes an inlet in which an integrated circuit portionformed from a MOS transistor or the like and an antenna are sealed, orsuch an inlet which is formed into a seal shape or a card shape. Whenthe area of the top face of the RFID is 4 mm² or more, further 9 mm² ormore, the antenna can be formed with a large size, so that an RFIDhaving a long communication distance with respect to a communicationinstrument can be manufactured.

Further, here, in the element substrate 1102 including a semiconductorelement formed using a single-crystal semiconductor substrate or an SOIsubstrate, the following are shown: the MOS transistors 1060 a and 1060b; an insulating layer 106 which covers the MOS transistors 1060 a and1060 b; conductive layers 108 and 109 which are connected to a sourceregion and a drain region in the MOS transistor 1060 a and to a sourceregion or a drain region in a well region of the MOS transistor 1060 b,through the insulating layer 106; and an insulating layer 111 whichcovers the conductive layers 108 and 109 and part of the insulatinglayer 106. The antenna 112 connected to the conductive layer 109 throughthe insulating layer 111 is formed over the element substrate 1102.

MOS transistor 1060 a at least includes a semiconductor substrate 101,impurity regions 1054 a, a gate insulating layer 1055 a, and a gateelectrode 1056 a. Further, the MOS transistor 1060 b includes a wellregion, impurity regions 1054 b a gate insulating layer 1055 b, and agate electrode 1056 b. If the semiconductor substrate 101 is n-type, ap-well region 1053 into which a p-type impurity has been injected isformed as the well region. As the p-type impurity, for example, boronmay be added at a concentration of approximately 5×10¹⁵ cm⁻³ to 1×10¹⁶cm⁻³. The provision of the p-well region 1053 makes it possible to forman n-channel transistor therein. Further, the p-type impurity added tothe p-well region 1053 has a function of controlling the thresholdvoltage of the MOS transistor. Channel formation regions to be formed inthe semiconductor substrate 101 and the p-well region 1053 are formed inregions which are approximately aligned with the gate electrodes 1056 aand 1056 b, respectively, and placed between pairs of impurity regions1054 a and 1054 d formed in the semiconductor substrate 101, and pairsof impurity regions 1054 b and 1054 e formed in the p-well region 1053,respectively.

The pairs of impurity regions 1054 a and 1054 b are regions serving assources and drains in the MOS transistors. The pairs of impurity regions1054 a and 1054 b are formed by doping with phosphorus or arsenic whichare n-type impurities and boron that is a p-type impurity, respectivelyat a peak concentration of approximately 10 cm⁻³.

Spacers 1057 a and 1057 b are formed on sidewalls of the gate electrodes1056 a and 1056 b, respectively. When the spacers 1057 a and 1057 b areformed, an advantageous effect is obtained in that leakage current atedges of the gate electrodes 1056 a and 1056 b is prevented. Inaddition, with the use of the spacers 1057 a and 1057 b, the lowconcentration impurity regions 1054 d and 1054 e can be formed underboth edges of the gate electrodes 1056 a and 1056 b in a channel lengthdirection, respectively. Each of the low concentration impurity regions1054 d and 1054 e serves as a lightly doped drain (LDD). The lowconcentration impurity regions 1054 d and 1054 e are not necessarilyformed; however, when these regions are provided, an electric field ofan edge of a drain can be moderated and deterioration of the MOStransistor can be suppressed.

The gate insulating layers 1055 a and 1055 b can be formed of, forexample, silicon oxide films obtained by oxidizing a surface of thesemiconductor substrate 101 with thermal treatment. Alternatively, thegate insulating layers 1055 a and 1055 b may be formed with a structurehaving a stack of a silicon oxide film and a film containing oxygen andnitrogen (a silicon oxynitride film) by forming the silicon oxide filmwith a thermal oxidation method and then nitriding the surface of thesilicon oxide film with nitridation treatment. The gate insulatinglayers 1055 a and 1055 b are formed from an inorganic insulator such asa silicon oxide or a silicon nitride oxide to a thickness of 5 nm to 50nm.

It is preferable that the gate electrodes 1056 a and 1056 b be formed ofmetal selected from tantalum (Ta), tungsten (W), titanium (Ti),molybdenum (Mo), chromium (Cr), niobium (Nb), and the like, or an alloymaterial or compound material containing any of the elements as its maincomponent. Alternatively, polycrystalline silicon to which an impurityelement such as phosphorus is added can be used. Further alternatively,a control gate electrode may be formed with a layered structure having astack of one or more metal nitride layers and a metal layer containingany of the above-described metals. As the metal nitride, a tungstennitride, a molybdenum nitride, or a titanium nitride can be used. Whenthe metal nitride layer is provided, adhesiveness of the metal layerformed on the metal nitride layer can be increased; accordingly,separation can be prevented.

An insulating layer 106 serves as an interlayer insulating layer forinsulating a MOS transistor and a conductive layer serving as a wiring.The insulating layer 106 can be formed of either a single layer or alaminate of an insulating layer containing oxygen or nitrogen, such as asilicon oxide, a silicon nitride, a silicon oxynitride, or a siliconnitride oxide; a layer containing carbon such as DLC (diamond-likecarbon); an organic material such as epoxy, polyimide, polyamide,polyvinyl phenol, benzocyclobutene, or acrylic; or a siloxane materialsuch as a siloxane resin, by CVD, sputtering, or the like.

Conductive layers 108 and 109 each serve as a wiring, a plug, or thelike. The conductive layers 108 and 109 are formed in a single layer ora laminate of an element selected from aluminum (Al), tungsten (W),titanium (Ti), tantalum (Ta), molybdenum (Mo), nickel (Ni), platinum(Pt), copper (Cu), gold (Au), silver (Ag), manganese (Mn), neodymium(Nd), carbon (C), and silicon (Si), or an alloy material or a compoundmaterial containing any of the element as its main component by CVD,sputtering, or the like. An alloy material containing aluminum as itsmain component corresponds to, for example, a material which containsaluminum as its main component and also contains nickel, or a materialwhich contains aluminum as its main component and also contains nickeland one or both of carbon and silicon. The conductive layers 108 and 109are preferably formed with a layered structure having a stack of abarrier film, an aluminum silicon (Al—Si) film, and a barrier film or alayered structure having a barrier film, an aluminum silicon (Al—Si)film, a titanium nitride (TiN) film, and a barrier film. Note that a“barrier film” corresponds to a thin film formed of titanium, a nitrideof titanium, molybdenum, or a nitride of molybdenum. Aluminum andaluminum silicon are suitable materials for forming the conductivelayers 108 and 109 because they have low resistance and are inexpensive.When barrier films are provided as the top layer and the bottom layer,generation of hillocks of aluminum or aluminum silicon can be prevented.In addition, when a barrier film is formed of titanium which is anelement having a high reducing property, even when a thin natural oxidefilm is formed over a semiconductor substrate, the natural oxide filmcan be reduced, and a favorable contact between the conductive layer andthe semiconductor substrate can be obtained.

An insulating layer serving as a protective film may be formed over theconductive layer 109 and the insulating layer 106. The insulating layeris formed from silicon nitride, silicon oxynitride, silicon nitrideoxide, carbon nitride, DLC, or the like. If ion-assisted deposition isperformed to form the protective film, a dense protective film can beobtained. When the insulating layer serving as a protective film isprovided, intrusion of moisture from outside into a MOS transistor canbe suppressed, in particular, the provision of a dense protective filmmakes the advantageous effect. Accordingly, the reliability of electriccharacteristics of the MOS transistor and a semiconductor device can beenhanced.

Further, over the insulating layer 106, one pair or plural pairs of aconductive layer and an insulating layer which insulates the conductivelayer may be formed in a multilayer structure. With a multilayerstructure, high integration is possible.

The antenna 112 is formed in such a manner that a droplet or paste whichincludes any one or more of metal particles of silver (Ag), gold (Au),copper (Cu), nickel (Ni), platinum (Pt), palladium (Pd), tantalum (Ta),molybdenum (Mo), titanium (Ti), and the like is discharged by a dropletdischarge method (an ink-jet method, a dispensing method, or the like),and it is dried and baked. When the antenna is formed by a dropletdischarge method, the number of process steps can be reduced, and costcan be reduced accordingly.

Further, the antenna 112 may be formed by a screen printing method. Inthe case of using a screen printing method, as a material for theantenna 112, a conductive paste in which conductive particles having aparticle size of several nanometers to several tens of micrometers aredissolved or dispersed in an organic resin is selectively printed. Asthe conductive particles, metal particles of one or more of silver (Ag),gold (Au), copper (Cu), nickel (Ni), platinum (Pt), palladium (Pd),tantalum (Ta), molybdenum (Mo), titanium (Ti), and the like, fineparticles of silver halide, or dispersing nanoparticles can be used. Inaddition, as the organic resin included in the conductive paste, one ormore selected from organic resins functioning as a binder, a solvent, adispersive agent, and a coating member of the metal particles can beused. Typically, an organic resin such as an epoxy resin or a siliconeresin can be given. Further, in forming the conductive layer, baking ispreferably performed after the conductive paste is pushed out.

Alternatively, the antenna 112 may be formed using gravure printing orthe like instead of a screen printing method or may be formed from aconductive material by a plating method, sputtering, or the like.

Here, the antenna 112 is formed in such a manner that an aluminum layeris formed by sputtering, and then, the aluminum layer is selectivelyetched using a resist mask formed by a photolithography process.

As a signal transmission method in an RFID, an electromagnetic couplingmethod or an electromagnetic induction method (for example, 13.56 MHzband) is applied. In the case of utilizing electromagnetic inductioncaused by a change in magnetic flux density, the top view of the antennacan be a ring shape (for example, a loop antenna) or a spiral shape (forexample, a spiral antenna).

Alternatively, a microwave method (for example, a UHF band (860 MHz to960 MHz band), a 2.45 GHz band, or the like) can be employed as thesignal transmission method in an RFID. In that case, the length, shape,or the like of the antenna may be appropriately set in consideration ofa wavelength of an electromagnetic wave used for signal transmission.

FIGS. 9A to 9D each show an example of the antenna 112 of an RFID towhich a microwave method can be adapted. For example, the top view ofthe antenna can be a linear shape (for example, a dipole antenna (seeFIG. 9A)), a flat shape (for example, a patch antenna (see FIG. 9B)), aribbon shape (see FIGS. 9C and 9D), or the like. Further, the shape ofthe conductive layer serving as an antenna is not limited to a linearshape, and may be a curved shape, a meandering shape, or a shapecombining these, in consideration of the wavelength of anelectromagnetic wave.

The element substrate 1102 is preferably thinned by partially removing arear surface portion thereof. As a method for partially removing therear surface, physical polishing and chemical removal can be given.Physical polishing is performed in such a manner that a protective tapeis stuck on a front surface of a semiconductor substrate (a side where asemiconductor element is formed), and then, a rear surface of thesemiconductor substrate is mechanically ground, and the rear surface ispolished by chemical mechanical polishing. As chemical removal, dryetching using a gas such as SF₆ or CF₄; wet etching using a liquidmixture of hydrofluoric acid, nitric acid, and acetic acid, or anaqueous solution of potassium hydroxide; or the like can be given.Typically, the thickness of the element substrate 1102 is preferablygreater than or equal to 1 μm and less than or equal to 80 μm, morepreferably greater than or equal to 1 μm and less than or equal to 50μm, still more preferably greater than or equal to 1 μm and less than orequal to 20 μm, still more preferably greater than or equal to 1 μm andless than or equal to 10 μm, still more preferably greater than or equalto 1 μm and less than or equal to 5 μm. Alternatively, the elementsubstrate 1102 may be made thinner by separating part of thesemiconductor substrate.

The fibrous body 113 provided over one surface or opposing surfaces ofthe element substrate 1102 is a woven fabric or a nonwoven fabric whichuses high-strength fiber of an organic compound or an inorganiccompound, and the fibrous body 113 covers an entire surface of theelement substrate 1102. High-strength fiber is specifically fiber with ahigh elongation modulus or fiber with a high Young's modulus. As typicalexamples of high-strength fiber, polyvinyl alcohol fiber, polyesterfiber, polyamide fiber, polyethylene fiber, aramid fiber,polyparaphenylene benzobisoxazole fiber, glass fiber, carbon fiber, andthe like can be given. As the glass fiber, glass fiber using E glass, Sglass, D glass, Q glass, or the like can be used. It is to be noted thatthe fibrous body 113 may be formed from one or more kinds of theabove-described high-strength fiber.

The fibrous body 113 may be formed using a woven fabric which is wovenusing bundles of fiber (single yarn) (hereinafter, referred to as yarnbundles) for warp yarns and weft yarns, or a nonwoven fabric obtained bystacking yarn bundles of plural kinds of fiber in a random manner or inone direction. In the case of a woven fabric, a plain-woven fabric, atwilled fabric, a satin-woven fabric, or the like can be appropriatelyused.

The yarn bundle may have a circular shape or an elliptical shape incross section. As the yarn bundle, a yarn bundle may be used which hasbeen subjected to fiber opening with a high-pressure water stream,high-frequency vibration using liquid as a medium, continuous ultrasonicvibration, pressing with a roll, or the like. A yarn bundle which issubjected to fabric opening has a large width, can reduce the number ofsingle yarns in the thickness direction, and has an elliptical shape ora flat shape in its cross section. Further, by using a loosely twistedyarn as the yarn bundle, the yarn bundle is easily flattened and has anelliptical shape or a flat shape in cross section. Use of a yarn bundlehaving an elliptical shape or a flat shape in cross section in thismanner can make a thickness of the fibrous body 113 small. Accordingly,a thin semiconductor device can be manufactured. An effect of thepresent invention is observed when the width of the yarn bundle isgreater than or equal to 4 μm and less than or equal to 400 μm, morepreferably greater than or equal to 4 μm and less than or equal to 200μm. In principle, the width of the yarn bundle may be even narrower thanthat. An effect of the present invention is observed when the thicknessof the yarn bundle is greater than or equal to 4 μm and less than orequal to 20 μm. In principle, the thickness of the yarn bundle may beeven smaller than that. The width and the thickness depend on a materialof fiber.

In the drawings of this specification, the fibrous body 113 is shown asa woven fabric which is plain-woven using a yarn bundle having anelliptical shape in cross section. Although the size of the MOStransistors 1060 a and 1060 b is larger than that of a yarn bundle ofthe fibrous body 113, the MOS transistors 1060 a and 1060 b may besmaller than a yarn bundle of the fibrous body 113.

FIGS. 8A and 8B each show a top view of a woven fabric as the fibrousbody 113 which is woven using yarn bundles for warp yarns and weftyarns.

As shown in FIG. 8A, the fibrous body 113 is woven using warp yarns 113a spaced at regular intervals and weft yarns 113 b spaced at regularintervals. Such a fibrous body has a region without the warp yarns 113 aand the weft yarns 113 b (referred to as basket holes 113 c). In such afibrous body 113, the fibrous body is further impregnated with anorganic resin, whereby adhesiveness between the fibrous body 113 and theelement substrate can be further increased.

As shown in FIG. 8B, in the fibrous body 113, density of the warp yarns113 a and the weft yarns 113 b may be high and a proportion of thebasket holes 113 c may be low. Typically, the size of the basket hole113 c is preferably smaller than the area of a locally pressed portion.More typically, the basket hole 113 c preferably has a rectangular shapehaving a side with a length greater than or equal to 0.01 mm and lessthan or equal to 0.2 mm. When the basket hole 113 c of the fibrous body113 has such a small area, even when pressure is applied by a memberwith a sharp tip (typically, a writing material such as a pen or apencil), the pressure can be absorbed in the entire fibrous body 113.

Further, in order to enhance permeability of an organic resin into theinside of the yarn bundle, the fiber may be subjected to surfacetreatment. For example, as the surface treatment, corona discharge,plasma discharge, or the like for activating a surface of the fiber canbe given. Further, surface treatment using a silane coupling agent or atitanate coupling agent can be given.

Next, as shown in FIG. 1B, a composition containing an organic resin isapplied over the fibrous body 113 and the element substrate 1102 to forman organic resin layer 114. The organic resin layer 114 may be formed ofa thermosetting resin such as an epoxy resin, an unsaturated polyesterresin, a polyimide resin, a bismaleimide-triazine resin, or a cyanateresin. Further, a thermoplastic resin such as a polyphenylene oxideresin, a polyetherimide resin, or a fluorine resin can be used.Furthermore, a plurality of the above-described thermosetting resin andthermoplastic resin may be used. When the above-described organic resinis used, the fibrous body can be firmly fixed to the element substrateby thermal treatment. The higher the glass transition temperature of theorganic resin layer 114 is, the harder the organic resin layer 114 isdamaged by local pressure, which is preferable.

As a method of forming the organic resin layer 114, a printing method, acast method, a droplet discharge method, a dip coating method, or thelike can be used.

Here, the organic resin layer 114 is wholly or partially impregnatedwith the fibrous body 113. In other words, the fibrous body 113 isincluded in the organic resin layer 114. Thus, the adhesion between thefibrous body 113 and the organic resin layer 114 is increased.

Highly thermally-conductive filler may be dispersed in the organic resinlayer 114 or the yarn bundle of the fibrous body. As the highlythermally-conductive filler, an aluminum nitride, a bromine nitride, asilicon nitride, alumina, or the like can be given. As the highlythermally-conductive filler, a metal particle such as silver or coppercan also be given. When the highly thermally-conductive filler isincluded in the organic resin or the yarn bundle, heat generated in theelement substrate can be easily released to the outside. Accordingly,thermal storage of the semiconductor device can be suppressed, andmalfunction of the semiconductor device can be reduced.

The organic resin 114 is heated so that the organic resin 114 isplasticized or cured. In the case where the organic resin is an organicplastic resin, the organic resin which is plasticized is then cured bycooling to room temperature.

Consequently, as shown in FIG. 1C, the organic resin 114 becomes anorganic resin layer 121 with which the fibrous body 113 is impregnatedand which is firmly fixed to one side of the element substrate 1102 andone side of the antenna 112. It is to be noted that the organic resinlayer 121 and the fibrous body 113 which are firmly fixed to one side ofthe element substrate 1102 and one side of the antenna 112 arecollectively referred to as a sealing layer 120.

In the case where a plurality of semiconductor devices are included inthe element substrate 1102, the plurality of semiconductor devices maybe obtained by dividing the element substrate 1102 and the sealinglayers. Through such steps, a plurality of semiconductor devices can bemanufactured.

As described above a semiconductor device can be manufactured.

Note that a sealing layer may also be formed on the semiconductorsubstrate 101 side. A fibrous body 126 is provided over thesemiconductor substrate 101. The fibrous body 126 may use the fibrousbody 113 shown in FIG. 1A as appropriate. A composition containing anorganic resin is applied to the fibrous body 126 and the elementsubstrate 1102 to coat them and then the fibrous body 126 and theelement substrate 1102 are baked to form an organic resin layer. Theorganic resin layer may use the organic resin layer 114 shown in FIG. 1Bas appropriate. Next, the organic resin layer is heated to plasticize orcure the organic resin of the organic resin layer. In the case where theorganic resin is plastic, the plasticized organic resin is then cured bycooling to room temperature. Consequently, as shown in FIG. 1D, asealing layer 129 including an organic resin layer 128 with which afibrous body 126 is impregnated and which is formed on the semiconductorsubstrate 101 can be formed. That is, a semiconductor device providedwith the sealing layers 120 and 129 on opposing surfaces of the elementsubstrate 1102 can be manufactured.

The sealing layers 120 and 129 at this time are preferably formed fromthe same fibrous body and organic resin in order to reduce warpage.However, in the case where the front and the back are distinguished fromeach other, it is not necessary that the sealing layers 120 and 129 areformed from the same materials. In such a manner, the organic resin withwhich the fibrous body is impregnated is firmly fixed to the opposingsurfaces of the element substrate, whereby the element substrate can besupported by the fibrous body. Therefore, warpage of the semiconductordevice can be reduced, which makes it easy to mount the semiconductordevice on a laminate film, a seal, or the like.

The direction of the warp yarn or the weft yarn of the fibrous body ofthe sealing layer 120 formed over the element substrate 1102 and thedirection of the warp yarn or the weft yarn of the fibrous body of thesealing layer 129 may be deviated from each other by 30° or more and 60°or less, more preferably 40° or more and 50° or less. In this case,since stretching directions of the fibrous bodies provided on the frontand the back of the element substrate are different from each other,stretching due to local pressure is isotropic. Thus, destruction causedby local pressure can be further reduced.

Note that in FIG. 1A to 1D, the organic resin layer 114 is formed afterthe fibrous body 113 is provided over the element substrate 1102;alternatively, the fibrous body may be provided over the elementsubstrate 1102 and the organic resin layer 114 after the organic resinlayer 114 is formed over the element substrate 1102. Those steps will bedescribed below.

As shown in FIG. 2A, the element substrate 1102 using a single-crystalsemiconductor substrate or an SOI substrate is formed over thesemiconductor substrate 101, and an antenna 112 is formed over theelement substrate 1102. Next, the organic resin layer 114 is formed overthe element substrate 1102 and the antenna 112.

Next, as shown in FIG. 2B, the fibrous body 113 is provided over theelement substrate 1102 and the antenna 112. Here, the fibrous body 113is pressed against the organic resin layer 114, the fibrous body 113 canbe contained in the organic resin layer 114. Further, the fibrous body113 is impregnated with the organic resin.

The organic resin 114 is heated so that the organic resin 114 isplasticized or cured. In the case where the organic resin is an organicplastic resin, the organic resin which is plasticized is then cured bycooling to room temperature.

Consequently, as shown in FIG. 2C, the organic resin 114 becomes anorganic resin layer 121 with which the fibrous body 113 is impregnatedand which is firmly fixed to one side of the element substrate 1102 andone side of the antenna 112. It is to be noted that the organic resinlayer 121 and the fibrous body 113 which are firmly fixed to one side ofthe element substrate 1102 and one side of the antenna 112 arecollectively referred to as a sealing layer 120.

After that, as in FIG. 1D, the sealing layer 129 may be formed on thesemiconductor substrate 101.

As described above a semiconductor device can be manufactured.

Here, effects of the semiconductor device described in this embodimentmode will be described with reference to FIGS. 3A to 3D.

As shown in FIG. 3A, in a conventional semiconductor device 40, anelement substrate 41 including a semiconductor element formed using asingle-crystal semiconductor substrate or an SOI substrate is sealedwith films 43 a and 43 b using adhesive members 42 a and 42 b. Localpressure 44 is applied to a semiconductor device having such astructure.

As a result, as shown in FIG. 3B, a layer which forms the elementsubstrate 41, the adhesive members 42 a and 42 b, and the films 43 a and43 b are each stretched, and a curve with a small radius of curvature isgenerated in the pressed portion. Accordingly, the semiconductor elementincluded in the element substrate 41, a wiring, or the like are cracked,and the semiconductor device is destroyed.

However, in a semiconductor device 1050 described in this embodimentmode, as shown in FIG. 3C, a sealing layer formed of a fibrous bodyincluding an organic resin is provided on one side or opposite sides ofan element substrate 1051. The fibrous body is formed from high-strengthfiber, which has a high elongation modulus or a high Young's modulus.Accordingly, even when the local pressure 44 such as point pressure orlinear pressure is applied, the high-strength fiber is not stretched.Pressing force is dispersed throughout the fibrous body, and the wholesemiconductor device is curved. Thus, even when local pressure isapplied, a curve generated in the semiconductor device has a largeradius of curvature as shown in FIG. 3D, and the semiconductor elementincluded in the element substrate 1051, a wiring, and the like are notcracked, and accordingly, destruction of the semiconductor device can bereduced.

Further, when the element substrate 1051 is formed to have a smallthickness, the semiconductor device can be curved. Accordingly, the areaof the element substrate 1051 can be enlarged, and thus, steps ofmanufacturing the semiconductor device can be easily performed. In thecase where the semiconductor device is an RFID with a built-in antenna,the size of the antenna can be increased. Thus, an RFID with a longcommunication distance can be manufactured.

In the case where a plurality of semiconductor devices are included inthe element substrate 1102, the plurality of semiconductor devices maybe obtained by dividing the element substrate 1102 and the sealinglayers. With such a step, a plurality of semiconductor devices can bemanufactured. When the division is performed, selective division ispossible by dicing, scribing, using a cutting machine having an edgedtool such as scissors or a knife, laser cutting, or the like.

Further, paper including a semiconductor device can be formed byembedding the semiconductor device. Specifically, the semiconductordevice is provided on a first wet paper. A second wet paper is disposedon thereon and pressing and drying are performed. As a result, paperincluding a semiconductor device can be formed. After that, the papermay be cut into the appropriate size.

In a semiconductor device described in this embodiment mode, an elementsubstrate having a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate and a fibrous body arefirmly fixed together with an organic resin. Since local pressureapplied to the fibrous body is dispersed throughout the fibrous body,local pressure is hardly applied. Accordingly, a wiring or asemiconductor element included in the semiconductor device is notstretched and the semiconductor device is not easily destroyed. That is,stretching of the semiconductor element, the wiring, or the like formedin the element substrate can be reduced, and thus, a yield can beimproved.

Further, when the element substrate is formed to have a small thickness,the semiconductor device can be curved. Accordingly, the area of theelement substrate can be enlarged, and thus, steps of manufacturing thesemiconductor device can be easily performed. In the case where thesemiconductor device is an RFID with a built-in antenna, the size of theantenna can be increased. Thus, an RFID with a long communicationdistance can be manufactured.

Embodiment Mode 2

In this embodiment mode, a manufacturing method of a semiconductordevice which is not easily destroyed as compared with the one inEmbodiment Mode 1, with reference to FIGS. 4A to 4C.

In a similar manner to Embodiment Mode 1, as shown in FIG. 4A, anantenna 112 and an element substrate 1102 including a semiconductorelement formed using a single-crystal semiconductor substrate or an SOIsubstrate are formed. Then, a fibrous body 113 is provided over theelement substrate 1102 and the antenna 112, an organic resin layer 114is formed, and a protective film 131 is provided over the organic resinlayer 114.

The protective film 131 is preferably formed from a high-strengthmaterial. As typical examples of a high-strength material, a polyvinylalcohol resin, a polyester resin, a polyamide resin, a polyethyleneresin, an aramid resin, a polyparaphenylene benzobisoxazole resin, aglass resin, and the like can be given.

Since the protective film 131 is formed from a high-strength material,destruction by local pressure can be suppressed compared with EmbodimentMode 1. In specific, in a fibrous body 113, in the case where the areaof a basket hole in which a warp yarn bundle and a weft yarn bundle arenot distributed is larger than the area to which local pressure isapplied, when the basket hole is locally loaded, the pressure is notabsorbed in the fibrous body 113 but is directly applied to the elementsubstrate 1102 and the antenna 112. As a result, the element substrate1102 and the antenna 112 are stretched, and the semiconductor element orthe wiring is destroyed.

However, by providing over the organic resin layer 114 the protectivefilm 131 formed from a high-strength material, a local load is absorbedin the entire protective film 131, leading to a semiconductor devicewhich is not easily destroyed by local pressure.

Next, as shown in FIG. 4B, in a similar manner to Embodiment Mode 1, theorganic resin layer 114 is heated, so that a sealing layer 120 isformed. The protective film 131 is firmly fixed to the element substrate1102 and the antenna 112 by an organic resin of the sealing layer 120.That is, the fibrous body 113 and the protective film 131 are firmlyfixed to the element substrate 1102 and the antenna 112 by the sealinglayer 120. The fibrous body 113 is impregnated with the organic resinlayer 121 included in the sealing layer 120.

Next, as shown in FIG. 4C, the following steps may be performed: thesemiconductor substrate 101 of the element substrate 1102 is providedwith a fibrous body, an organic resin layer is formed, a protective film141 is provided, and heating and pressure bonding is performed to firmlyfix the protective film 141 to the element substrate 1102 using thesealing layer 129.

In FIG. 4A, in the case where the protective film 131 is a thermoplasticmaterial, the protective film 131 may alternatively be provided betweenthe element substrate 1102 and the antenna 112, and the fibrous body113, and thermocompression bonding may be performed. Alternatively,protection film 131 may be provided between the fibrous body 113 and theorganic resin layer 114, the element substrate 1102, and the antenna112, and thermocompression bonding may be performed. In FIG. 4C, in thecase where the protective film 141 is a thermoplastic material, theprotective film 141 may be provided between the element substrate 1102and the fibrous body, and thermocompression bonding may be performed.Further, the protective film 141 may be provided between the elementsubstrate 1102 and the fibrous body, and the organic resin layer, andthermocompression bonding may be performed. This structure also makes itpossible to disperse the load applied by local pressure using theprotection film and the fibrous body, thus, destruction can besuppressed.

In the case where a plurality of semiconductor devices are included inthe element substrate 1102, the plurality of semiconductor devices maybe obtained by dividing the element substrate 1102 and the sealinglayers. Through such steps, a plurality of semiconductor devices can bemanufactured.

Further, as in Embodiment Mode 1, paper including a semiconductor devicecan be formed by embedding the semiconductor device.

In a manner described above, a semiconductor device which is not easilydestroyed by local pressure can be manufactured. Further, when theelement substrate is formed to have a small thickness, the semiconductordevice can be curved. Accordingly, the area of the element substrate canbe enlarged, and thus, steps of manufacturing the semiconductor devicecan be easily performed. In the case where the semiconductor device isan RFID with a built-in antenna, the size of the antenna can beincreased. Thus, an RFID with a long communication distance can bemanufactured.

Embodiment Mode 3

In this embodiment mode, a method for manufacturing a semiconductordevice in which an antenna is not formed in an element substrate and anantenna provided over another substrate is connected to the elementsubstrate will be described with reference to FIG. 5A to FIG. 7C.

As shown in FIG. 5A, a fibrous body 113 and an organic resin layer 155having an opening 154 are formed over an element substrate 1151.

Here, as the element substrate 1151, as described in Embodiment Mode 1,the semiconductor substrate 101 is provided with the MOS transistors1060 a and 1060 b. An insulating layer 106 is formed over the MOStransistors 1060 a and 1060 b, and conductive layers 108 and 109 whichconnect to a source region and a drain region of the MOS transistors areformed through the insulating layer 106. An insulating layer 111 isformed over the conductive layers 108 and 109 and the insulating layer106, and an electrode pad 152 is formed so as to connect to theconductive layer 109 through the insulating layer 111.

The organic resin layer 155 is formed so as to have an opening 154 inwhich part of the electrode pad 152 is exposed, by providing acomposition in which an organic resin is diluted with an organic solventover the element substrate 1151 by a printing method or a dropletdischarge method and performing drying by baking.

As shown in FIG. 5B, a connection terminal 161 is formed in an openingin the organic resin layer 155. The connection terminal 161 can beformed by a printing method, a droplet discharge method, or the like. Asa material for the connection terminal 161, at least one of metalparticles of silver (Ag), gold (Ag), copper (Cu), nickel (Ni), platinum(Pt), palladium (Pd), tantalum (Ta), molybdenum (Mo), and titanium (Ti);fine particles of silver halide; or dispersive nanoparticles can beused. Next, the material of the connection terminal is baked to form asealing layer 156 including the organic resin layer 155 and the fibrousbody 113 on one side surface of the element substrate 1151. Note thatthe sealing layer 156 is provided with the connection terminal 161 whichconnects to the electrode pad 152.

Then, as shown in FIG. 5C, the sealing layer 156 which is firmly fixedto the element substrate 1151 and a substrate 171 provided with anantenna 172 are bonded together by with an adhesive 174. At this time,the connection terminal 161 which is formed on the element substrate1151 and the antenna 172 are electrically connected to each other by ananisotropic conductive adhesive member 173.

As the anisotropic conductive adhesive member 173, an adhesive resincontaining conductive particles (each grain size is several nanometersto several tens of micrometers), which are dispersed, such as an epoxyresin or a phenol resin can be given. The conductive particle is formedfrom one or more elements selected from gold, silver, copper, palladium,nickel, carbon, and platinum. Further, a particle having a multilayerstructure of these elements may be used. Furthermore, a conductiveparticle in which a thin film which is formed from one or more elementsselected from gold, silver, copper, palladium, nickel, and platinum isformed over a surface of a particle formed from a resin may be used.Further alternatively, a CNT (carbon nanotube) may be used as theconductive particle.

The antenna 172 can be appropriately formed using a material and aformation method which are similar to those of the antenna 112 describedin Embodiment Mode 1.

As the substrate 171 over which the antenna 172 is formed, a plasticfilm substrate, for example, a plastic substrate of polyethyleneterephthalate (PET), polyether sulfone (PES), polyethylene naphthalate(PEN), polycarbonate (PC), nylon, polyetheretherketone (PEEK),polysulfone (PSF), polyether-imide (PEI), polyarylate (PAR),polybutylene terephthalate (PBT), or the like can be used.

Then, as shown in FIG. 6A, in a similar manner to Embodiment Mode 1, asealing layer 129 may be formed over a surface of the semiconductorsubstrate 101.

Then, as shown in FIG. 6B, a film 175 may be provided so as to seal thesubstrate 171 over which the antenna 172 is formed, the sealing layer156, the element substrate 1151, and the sealing layer 129. The film canbe a film similar to that of the substrate 171 over which the antenna172 is formed.

The above mode describes a semiconductor device in which the substrate171 having the antenna 172 is bonded to only one surface of the elementsubstrate 1151; however, the substrates over each of which the antennais formed may be bonded to opposing surfaces of the element substrate1151. The mode is described with reference to FIGS. 7A to 7C.

In an element substrate 1181, as described in Embodiment Mode 1, the MOStransistors 1060 a and 1060 b are formed in a semiconductor substrate101. An insulating layer 106 is formed over the MOS transistors 1060 aand 1060 b, and conductive layers 108 and 109 which are connected to asource region and a drain region of the MOS transistor through theinsulating layer 106 are formed. An insulating layer 111 is formed overthe conductive layers 108 and 109 and the insulating layer 106, and anelectrode pad 152 and a conductive layer 153 which are connected to theconductive layer 109 through the insulating layer 111 are formed.

Then, a through hole is formed in the semiconductor substrate 101, theinsulating layer 106, and the insulating layer 111. A through electrode183 is formed on a surface of the through hole. The through electrode183 is in contact with the conductive layer 153. The through electrode183 is insulated from the semiconductor substrate 101 by an insulatinglayer 184.

After that, a connection terminal 161 is formed by a similar step toFIGS. 5A and 5B on one surface of the element substrate 1181. Then, by astep similar to FIG. 5C, a substrate 171 on which an antenna 172 isformed and a sealing layer 156 provided on one surface of the elementsubstrate 1181 are bonded together with the adhesive 174.

A fibrous body is provided over the semiconductor substrate 101 of theelement substrate 1181 and an organic resin layer is formed, and then,heating is performed to form a sealing layer 125. Next, in order to forma connection terminal which is connected to the through electrode 183,an opening is formed in part of the sealing layer 125. Here, the openingpenetrating through the sealing layer 125 to the through electrode 183is formed by laser irradiation to expose part of the through electrode183.

Then, as shown in FIG. 7B, a connection terminal 186 is formed so as tofill the opening. The connection terminal 186 can be formed in a similarmanner to the connection terminal 161.

As shown in FIG. 7C, the sealing layer 129 and a substrate 191 providedwith an antenna 192 are bonded together, and the connection terminal 186and the antenna 192 are electrically connected to each other by ananisotropic conductive adhesive member 193.

In a manner described above, a semiconductor device in which opposingsurfaces of the element substrate are provided with antennas can bemanufactured. Such a semiconductor device is preferably applied to thesemiconductor device having a symmetrical antenna such as an RFIDcapable of receiving an electric wave of a UHF band, because the size ofthe semiconductor device can be reduced.

In the case where a plurality of semiconductor devices are included ineach of the element substrates 1151 and 1181, the plurality ofsemiconductor devices may be obtained by dividing the element substrates1151 and 1181 and the sealing layers. Through such steps, a plurality ofsemiconductor devices can be manufactured.

Further, as in Embodiment Mode 1, paper including a semiconductor devicecan be formed by embedding the semiconductor device.

In a semiconductor device described in this embodiment mode, an elementsubstrate having a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate and a fibrous body arefirmly fixed together by an organic resin. In the fibrous body, pressuregiven by local pressing is dispersed throughout fiber; thus, localpressure is not easily applied. Accordingly, a wiring or a semiconductorelement included in the semiconductor device are not stretched and thesemiconductor device is not easily destroyed. That is, stretching of thesemiconductor element formed in the element substrate, the wiring, orthe like can be reduced, and thus, a yield can be improved.

Further, when the element substrate is formed to have a small thickness,the semiconductor device can be curved. Accordingly, the area of theelement substrate can be enlarged, and thus, steps of manufacturing thesemiconductor device can be easily performed because a connection areafor connecting an external antenna to the element substrate can beenlarged. In the case where the semiconductor device is an RFID with abuilt-in antenna, the size of the antenna can be increased. Thus, anRFID with a long communication distance can be manufactured.

Embodiment Mode 4

This embodiment mode describes a semiconductor device in which any ofthe element substrates, which are described in Embodiment Modes 1 to 3,including a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate is connected to a printedboard, with reference to FIGS. 10A and 10B.

FIG. 10A is a perspective view of a semiconductor device 250 of thisembodiment mode. In the semiconductor device 250, an element substrateincluding a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate, which is described inEmbodiment Modes 1 to 3, is provided for a flexible printed board. Forexample, a wiring 252 formed from copper, gold, silver, aluminum, or thelike is provided over a base film 251 formed from polyester, polyimide,or the like. Stacks 253 a and 253 b, in each of which the elementsubstrate including a semiconductor element formed using asingle-crystal semiconductor substrate or an SOI substrate, which isdescribed in Embodiment Modes 1 to 3, and a sealing layer are stackedare provided over the wiring 252 with an insulating layer interposedbetween the wiring 252 and the stacks 253 a and 253 b. The wiring 252 isconnected to the stacks 253 a and 253 b through a connection terminalformed in a contact hole of the sealing layer. Part of the base film251, part of the wiring 252, and the stacks 253 a and 253 b are coveredwith a protective film 254. In an edge portion of the semiconductordevice 250, part of the protective film 254 is removed, and an externalcircuit such as a connector and the wiring 252 are exposed.

The element substrate is provided for a base substrate with the sealinglayer interposed therebetween, and the element substrate can be firmlyfixed to the wiring and a base substrate by heating and pressurebonding.

Here, a semiconductor device having the wiring 252 of one layer isdescribed below. Alternatively, a multilayer wiring structure may beemployed. Further, a plurality of wirings may interpose the stacks 253 aand 253 b. Such a multilayer wiring can increase packing density.

FIG. 10B is a cross-sectional view of a semiconductor device 260 of thisembodiment mode. In the semiconductor device 260, an element substrateincluding a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate, which is described inEmbodiment Modes 1 to 3, is provided on a printed board. For example, anelement substrate 262 including a semiconductor element formed using asingle-crystal semiconductor substrate or an SOI substrate, which isdescribed in Embodiment Modes 1 to 3, is provided on one surface of acore layer 261. A wiring or a semiconductor element included in theelement substrate 262 including a semiconductor element formed using asingle-crystal semiconductor substrate or an SOI substrate, which isdescribed in Embodiment Modes 1 to 3, is connected to the core layer 261by a via 264 passing through a sealing layer 263.

A multilayer wiring 265 is provided on the element substrate 262. Thecore layer 261, and the semiconductor element, the wiring, and the likewhich are formed in the element substrate 262 are electrically connectedto a conductive pattern 268 formed on a surface of the semiconductordevice 260, by vias 267 formed in organic resin layers 266 of themultilayer wiring 265.

A multilayer wiring 269 is provided on the opposite surface of the corelayer 261.

In addition, a chip 271 such as a capacitor, a coil, a resistor, or adiode may be mounted on the semiconductor device 260 with the use of amounting member 272 such as a conductive paste or a wire.

In the semiconductor device of this embodiment mode, a printed board hasa layer including a semiconductor element formed using a single-crystalsemiconductor substrate or an SOI substrate. Further, the element layeris provided in a printed board with the use of a prepreg using a fibrousbody. Thus, even when a local load (point pressure, linear pressure, orthe like) is applied, pressure is dispersed in the fibrous body, anddestruction in a mounting step or generated by a curve can be reduced.Furthermore, high integration is possible.

Embodiment Mode 5

This embodiment mode describes a structure and an application example ofa semiconductor device of the present invention. Here, an RFID and amemory device are described as typical examples of a semiconductordevice.

First, a circuit structure example of an RFID 501, which is one of thesemiconductor devices of the present invention, is described. FIG. 11shows a circuit block diagram of the RFID 501.

The RFID 501 in FIG. 11 conforms to specifications of ISO 15693 of theInternational Organization for Standardization, and it is a vicinitytype, and has a communication signal frequency of 13.56 MHz. Further,reception only responds to a data reading instruction, data transmissionrate in transmission is about 13 kHz, and the Manchester code is usedfor a data encoding format.

A circuit portion 412 of the RFID 501 is roughly separated into a powersupply portion 460 and a signal processing portion 461. The power supplyportion 460 includes a rectifying circuit 462 and a storage capacitor463. Further, the power supply portion 460 may be provided with aprotection circuit portion (also called a limiter circuit) to protectthe internal circuit when the amount of electric power received by anantenna 411 is too large, and a protection circuit control circuitportion to control whether or not to operate the protection circuitportion. By providing the circuit portion, a malfunction can beprevented, which is caused by receiving the large amount of electricpower by the RFID under the situation or the like in which acommunication distance between the RFID and a communication instrumentis extremely short. Thus, reliability of the RFID can be improved. Thatis, the RFID can be normally operated without degradation of an elementin the RFID or destruction of the RFID itself.

Here, a communication instrument may have a means for transmitting andreceiving information to/from the RFID by wireless communication, andfor example, a reader which reads information, a reader/writer having afunction of reading and a function of writing, and the like can begiven. Further, a mobile phone, a computer, or the like having one of orboth the function of reading and the function of writing is alsoincluded.

The rectification circuit 462 rectifies a carrier wave received by theantenna 411 and generates direct-current voltage. The storage capacitor463 smoothes the direct-current voltage generated in the rectificationcircuit 462. The direct-current voltage generated in the power supplyportion 460 is supplied to each circuit of the signal processing portion461 as power supply voltage.

The signal processing portion 461 includes a demodulation circuit 464, aclock generation/correction circuit 465, a recognition/determinationcircuit 466, a memory controller 467, a mask ROM 468, an encodingcircuit 469, and a modulation circuit 470.

The demodulation circuit 464 is a circuit that demodulates a signalreceived by the antenna 411. The received signal that is demodulated inthe demodulation circuit 464 is input to the clock generation/correctioncircuit 465 and the recognition/determination circuit 466.

The clock generation/correction circuit 465 generates a clock signalthat is necessary for operating the signal processing portion 461, andalso has a function of correcting the clock signal. For example, theclock generation/correction circuit 465 includes a voltage controlledoscillator circuit (hereinafter referred to as “VCO circuit”), and turnsan output from the VCO circuit into a feedback signal, makes a phasecomparison with a supplied signal, and adjusts an output signal bynegative feedback so that the feedback signal and a signal that is inputare each in a certain phase.

The recognition/determination circuit 466 recognizes and determines aninstruction code. The instruction code that is recognized and determinedby the recognition/determination circuit 466 is an end-of-frame (EOF)signal, a start-of-frame (SOF) signal, a flag, a command code, a masklength, a mask value, or the like. Further, therecognition/determination circuit 466 has a cyclic redundancy check(CRC) function that identifies a transmission error.

The memory controller 467 reads data from a mask ROM based on a signalprocessed by the recognition/determination circuit 466. Further, an IDor the like is stored in the mask ROM 468. By mounting the mask ROM 468,the RFID 501 is formed to be dedicated to reading, so that replicationor falsification is impossible. Paper which is prevented from forgerycan be provided by embedding the RFID 501 dedicated to reading in paper.

The encoding circuit 469 encodes data that is read from the mask ROM 468by the memory controller 467. The encoded data is modulated in themodulation circuit 470. The data modulated in the modulation circuit 470is transmitted from the antenna 411 as data signals on a carrier wave.

Next, usage examples of an RFID are described. An RFID of the presentinvention can be used for various paper media and film media. Inparticular, the RFID of the present invention can be used for variouspaper media for which forgery prevention is necessary. The paper mediaare, for example, banknotes, family registers, residence certificates,passports, licenses, identification cards, membership cards, expertopinions in writing, patient's registration cards, commuter passes,promissory notes, checks, carriage notes, cargo certificates, warehousecertificates, stock certificates, bond certificates, gift certificates,tickets, deeds of mortgage, and the like.

Further, by implementing the present invention, a lot of information,more information than that which is visually shown on a paper medium,can be held in the paper medium or the film medium. Accordingly, byapplying the RFID of the present invention to a product label or thelike, electronic systemization of merchandise management or preventionof product theft can be realized. Usage examples of paper according tothe present invention are described below with reference to FIGS. 12A to12E.

FIG. 12A is an example of a bearer bond 511 using paper embedded with anRFID 501 of the present invention. The bearer bond 511 includes a stamp,a ticket, an admission ticket, a gift certificate, a book coupon, astationery coupon, a beer coupon, a rice coupon, various gift coupons,various service coupons, and the like, but of course, the bearer bond511 is not limited thereto. Also, FIG. 12B is an example of acertificate 512 using paper embedded with the RFID 501 of the presentinvention (for example, a residence certificate or a family register).

FIG. 12C is an example of applying the RFID of the present invention asa label. A label (ID sticker) 514 is formed of the paper embedded withthe RFID 501, over a label base (separate paper) 513. The label 514 isstored in a box 515. On the label 514, information regarding a productor a service (such as product name, brand, trademark, trademark owner,seller, or manufacturer) is printed. In addition, since a unique IDnumber of the product (or a category of the product) is stored in theRFID 501, forgery, infringement of intellectual property rights such asa trademark right or a patent right, and illegal activity such as unfaircompetition can be spotted easily. The RFID 501 can be input with alarge amount of information that cannot all be written on a container ora label of the product, such as the product's area of production, areaof sales, quality, raw material, effect, use, quantity, shape, price,production method, usage method, time of production, time of use,expiration date, instruction manual, and intellectual propertyinformation relating to the product, for example. Accordingly, atransactor or a consumer can access such information with a simplecommunication instrument. Further, the information can easily berewritten, erased, or the like on a producer side, but cannot berewritten, erased or the like on a transactor or consumer side.

FIG. 12D shows a tag 516 formed of paper or a film which is embeddedwith the RFID 501. By manufacturing a tag 516 with the paper or filmwhich is embedded with the RFID 501, the tag can be manufactured lessexpensively than a conventional ID tag using a plastic chassis. FIG. 12Eshows a book 517 using the paper of the present invention for a cover,and the RFID 501 is embedded in the cover.

By attaching to the product the label 514 or the tag 516 which areequipped with an RFID which is an example of a semiconductor device ofthe present invention, merchandise management becomes easy. For example,when the product is stolen, the perpetrator can be spotted quickly byfollowing a route of the product. In this manner, by using the RFID ofthe present invention for an ID tag, historical management of theproduct's raw material, area of production, manufacturing andprocessing, distribution, sales, and the like, as well as trackinginquiry becomes possible. That is, the product becomes traceable.Further, by the present invention, a tracing management system of theproduct can be introduced at lower cost than before.

An RFID which is an example of a semiconductor device of the presentinvention is not easily destroyed by local pressure. Accordingly, apaper medium and a film medium each having an RFID which is an exampleof a semiconductor device of the present invention can be curved in aprocess such as attachment or setting, leading to improvement oftreatment efficiency. Further, since information can be written with awriting material to a paper medium or a film medium each having an RFIDwhich is an example of a semiconductor device of the present invention,the range of uses is increased.

Next, a structure of a memory device which is one mode of asemiconductor device of the present invention is described below. Here,description is made by using a nonvolatile memory device as a typicalexample of a memory device.

FIG. 13 shows an example of a circuit block diagram of a nonvolatilesemiconductor memory device. The nonvolatile semiconductor memory deviceincludes a memory cell array 552 and a peripheral circuit 554 which areformed over the same element substrate. The memory cell array 552 has anonvolatile memory element as described in Embodiment Mode 1. Astructure of the peripheral circuit 554 is as described below.

A row decoder 562 for selecting a word line and a column decoder 564 forselecting a bit line are provided around the memory cell array 552. Anaddress is sent to a control circuit 558 through an address buffer 556,and an inner row address signal and an inner column address signal aretransferred to the row decoder 562 and the column decoder 564,respectively.

Potential obtained by boosting power supply potential is used forwriting and erasing of data. Therefore, a booster circuit 560 controlledby the control circuit 558 according to an operation mode is provided.Output of the booster circuit 560 is supplied to a word line or a bitline through the row decoder 562 and the column decoder 564. Data outputfrom the column decoder 564 is input to a sense amplifier 566. Data readby the sense amplifier 566 is retained in a data buffer 568. Dataretained in the data buffer 568 is accessed randomly by control by thecontrol circuit 558, and is output through a data input/output buffer570. Writing data is once retained in the data buffer 568 through thedata input/output buffer 570 and is transferred to the column decoder564 by control by the control circuit 558.

As described above, in the nonvolatile semiconductor memory device,potential that differs from the power supply potential is necessary tobe used in the memory cell array 552. Therefore, it is desirable that atleast the memory cell array 552 and the peripheral circuit 554 beelectrically insulated and isolated. In this case, when a nonvolatilememory element and a transistor of a peripheral circuit are formed usinga single-crystal semiconductor layer formed over an insulating surface,insulation and isolation can be easily performed. Accordingly, anonvolatile semiconductor memory device with no malfunction and lowpower consumption can be obtained.

Embodiment Mode 6

This embodiment mode describes an electronic device using asemiconductor device of the present invention.

As electronic devices to which a semiconductor device of the presentinvention is applied, cameras such as video cameras or digital cameras,goggle displays (head mounted displays), navigation systems, audioreproducing devices (e.g., car audio or audio component sets),computers, game machines, portable information terminals (e.g., mobilecomputers, mobile phones, portable game machines, or electronic books),and image reproducing devices provided with storage media (specifically,a device for reproducing the content of a storage medium such as a DVD(Digital Versatile Disc) and having a display for displaying thereproduced image) can be given. FIGS. 14A to 14E show specific examplesof such electronic devices.

FIGS. 14A and 14B show digital cameras. FIG. 14B shows a rear side ofFIG. 14A. This digital camera includes a housing 2111, a display portion2112, a lens 2113, operating keys 2114, a shutter button 2115, and thelike. A semiconductor device 2116 of the present invention which has afunction as a storage device, an MPU, an image sensor, or the like isprovided inside the housing 2111.

FIG. 14C shows a mobile phone which is one typical example of a portableterminal. This mobile phone includes a housing 2121, a display portion2122, operating keys 2123, and the like. A semiconductor device 2125 ofthe present invention which has a function as a storage device, an MPU,an image sensor, or the like is provided inside the mobile phone.

FIG. 14D shows a digital player which is one typical example of an audiodevice. The digital player shown in FIG. 14D includes a main body 2130,a display portion 2131, a semiconductor device 2132 of the presentinvention which has a function as a storage device, an MPU, an imagesensor, or the like, an operating portion 2133, a pair of earphones2134, and the like.

FIG. 14E shows an e-book device (also called an electronic paper). Thise-book device includes a main body 2141, a display portion 2142,operating keys 2143, and a semiconductor device 2144 of the presentinvention which has a function as a storage device, an MPU, an imagesensor, or the like. In addition, a modem may be built into the mainbody 2141, or a structure capable of wireless data transmission andreception may be employed.

In a manner described above, the applicable range of the semiconductordevice of the present invention is so wide that the semiconductor devicecan be applied to other electronic devices.

This application is based on Japanese Patent Application serial no.2007-079264 filed with Japan Patent Office on Mar. 26, 2007, the entirecontents of which are hereby incorporated by reference.

1. A method of manufacturing a semiconductor device, comprising thesteps of: providing a fibrous body over an element substrate, whereinthe element substrate has an active element; applying a compositioncontaining an organic resin over the element substrate; and forming asealing layer including the fibrous body and the organic resin byheating the element substrate.
 2. The method of manufacturing asemiconductor device according to claim 1, wherein the fibrous body isimpregnated with the organic resin.
 3. The method of manufacturing asemiconductor device according to claim 1 further comprising a step offorming an insulating layer which covers the active element.
 4. Themethod of manufacturing a semiconductor device according to claim 1further comprising a step of forming an antenna over the elementsubstrate.
 5. The method of manufacturing a semiconductor deviceaccording to claim 1, wherein the element substrate is formed using anSOI substrate.
 6. The method of manufacturing a semiconductor deviceaccording to claim 1, wherein the active element is one or more of a MOStransistor, a nonvolatile memory element, and a diode.
 7. The method ofmanufacturing a semiconductor device according to claim 1, wherein thefibrous body comprises glass fiber.
 8. The method of manufacturing asemiconductor device according to claim 1, wherein the organic resin isa thermosetting resin.
 9. A method of manufacturing a semiconductordevice, comprising the steps of: providing a first fibrous body over afirst surface of an element substrate, wherein the element substrate hasan active element; applying a first composition containing a firstorganic resin from above the first fibrous body and the elementsubstrate so that the first fibrous body is impregnated with the firstorganic resin; and forming a first sealing layer including the firstfibrous body and the first organic resin by heating the elementsubstrate, after applying the first composition.
 10. The method ofmanufacturing a semiconductor device according to claim 9 furthercomprising a step of forming an insulating layer which covers the activeelement.
 11. The method of manufacturing a semiconductor deviceaccording to claim 9 further comprising a step of forming an antennaover the element substrate.
 12. The method of manufacturing asemiconductor device according to claim 9, wherein the element substrateis formed using an SOI substrate.
 13. The method of manufacturing asemiconductor device according to claim 9, wherein the active element isone or more of a MOS transistor, a nonvolatile memory element, and adiode.
 14. The method of manufacturing a semiconductor device accordingto claim 9, wherein the first fibrous body comprises glass fiber. 15.The method of manufacturing a semiconductor device according to claim 9further comprising the steps of: providing a second fibrous body over asecond surface of the element substrate, the second surface opposed tothe first surface of the element substrate; applying a secondcomposition containing a second organic resin to the second fibrous bodyand the element substrate so that the second fibrous body is impregnatedwith the second organic resin; and forming a second sealing layerincluding the second fibrous body and the second organic resin byheating the element substrate, after applying the second composition.16. The method of manufacturing a semiconductor device according toclaim 15, wherein the second fibrous body comprises glass fiber.
 17. Amethod of manufacturing a semiconductor device, comprising the steps of:forming a first organic resin layer over a first surface of an elementsubstrate, wherein the element substrate has an active element;providing a first fibrous body on the first organic resin layer and theelement substrate so that the first fibrous body is impregnated with afirst organic resin of the first organic resin layer; and forming afirst sealing layer including the first fibrous body and the firstorganic resin by heating the element substrate, after providing thefirst fibrous body.
 18. The method of manufacturing a semiconductordevice according to claim 17 further comprising a step of forming aninsulating layer which covers the active element.
 19. The method ofmanufacturing a semiconductor device according to claim 17 furthercomprising a step of forming an antenna over the element substrate. 20.The method of manufacturing a semiconductor device according to claim17, wherein the element substrate is formed using an SOI substrate. 21.The method of manufacturing a semiconductor device according to claim17, wherein the active element is one or more of a MOS transistor, anonvolatile memory element, and a diode.
 22. The method of manufacturinga semiconductor device according to claim 17, wherein the first fibrousbody comprises glass fiber.
 23. The method of manufacturing asemiconductor device according to claim 17 further comprising the stepsof: forming a second organic resin layer over a second surface of theelement substrate, the second surface opposed to the first surface ofthe element substrate; providing a second fibrous body on the secondorganic resin layer and the element substrate so that the second fibrousbody is impregnated with a second organic resin of the second organicresin layer; and forming a second sealing layer including the secondfibrous body and the second organic resin by heating the elementsubstrate, after providing the second fibrous body.
 24. The method ofmanufacturing a semiconductor device according to claim 23, wherein thesecond fibrous body comprises glass fiber.
 25. A method of manufacturinga semiconductor device, comprising the steps of: providing a firstfibrous body over a first surface of an element substrate, wherein theelement substrate has an active element and a first wiring; applying afirst composition containing a first organic resin from above the firstfibrous body and the element substrate so that the first fibrous body isimpregnated with the first organic resin; forming a first sealing layerincluding the first fibrous body and the first organic resin by heatingthe element substrate, after applying the first composition; forming afirst connection terminal connected to the first wiring in a firstopening of the first sealing layer; and bonding a first substrate havinga first antenna to the first sealing layer so that the first connectionterminal and the first antenna are electrically connected to each other.26. The method of manufacturing a semiconductor device according toclaim 25 further comprising the steps of: providing a second fibrousbody over a second surface of the element substrate, the second surfaceopposed to the first surface of the element substrate; applying a secondcomposition containing a second organic resin to the second fibrous bodyand the element substrate so that the second fibrous body is impregnatedwith the second organic resin; and forming a second sealing layerincluding the second fibrous body and the second organic resin byheating the element substrate, after applying the second composition.27. The method of manufacturing a semiconductor device according toclaim 26 further comprising the steps of: forming a second opening sothat part of a second wiring formed in the element substrate is exposed;forming a second connection terminal connected to the second wiring inthe second opening of the second sealing layer; and bonding a secondsubstrate having a second antenna to the second sealing layer so thatthe second connection terminal and the second antenna are electricallyconnected to each other.
 28. A method of manufacturing a semiconductordevice, comprising the steps of: forming a first organic resin layerover a first surface of an element substrate, wherein the elementsubstrate has an active element and a first wiring; providing a firstfibrous body on the first organic resin layer and the element substrateso that the first fibrous body is impregnated with a first organic resinof the first organic resin layer; forming a first sealing layerincluding the first fibrous body and the first organic resin by heatingthe element substrate, after providing the first fibrous body; forming afirst connection terminal connected to the first wiring in a firstopening of the first organic resin layer; and bonding a first substratehaving a first antenna to the first sealing layer so that the firstconnection terminal and the first antenna are electrically connected toeach other.
 29. The method of manufacturing a semiconductor deviceaccording to claim 28 further comprising the steps of: forming a secondorganic resin layer over a second surface of the element substrate;providing a second fibrous body on the second organic resin layer andthe element substrate so that the second fibrous body is impregnatedwith a second organic resin of the second organic resin layer; andforming a second sealing layer including the second fibrous body and thesecond organic resin by heating the element substrate, after providingthe second fibrous body.
 30. The method of manufacturing a semiconductordevice according to claim 29 further comprising the steps of: forming asecond opening so that part of a second wiring formed in the elementsubstrate is exposed; forming a second connection terminal connected tothe second wiring in the second opening of the second organic resinlayer; and bonding a second substrate having a second antenna to thesecond sealing layer so that the second connection terminal and thesecond antenna are electrically connected to each other.